Management of Tibial Rotation in Dogs with Medial Patellar Luxation Using Dynamic Antirotational External Fixation

Abstract

Objective

The aim of this study was to describe the clinical application and outcomes of a transarticular dynamic external skeletal fixator in the treatment of medial patellar luxation (MPL) associated with internal tibial rotation in dogs.

Study Design

Retrospective clinical case series.

Animals

Seventeen stifles in fifteen dogs of various breeds and sizes were treated for MPL and rotational tibial deformity using a dynamic external fixator over a 12-year period (2013–2025).

Methods

Clinical records were reviewed for signalment, MPL grade, surgical technique, treatment duration, and complications. The fixator consisted of a femoral and tibial threaded pins connected by elastic bands. Follow-up included clinical and radiographic evaluation of patellar stability and tibial rotation.

Results

Sixteen of seventeen stifles underwent trochlear intervention. Bilateral central threaded pins were used in 6 cases and unilateral pins in 11. The average fixation duration was 8.2 days. Twelve of the 13 dogs treated during the primary procedure showed no recurrence. Four dogs required revision surgery, which included reapplication of the dynamic fixator. No implant failures were observed.

Conclusion

The dynamic external skeletal fixator was effective in managing MPL with rotational tibial deformity. It provided controlled correction with low complication rates and proved useful both as a primary and a revision technique. These findings support further investigation into dynamic fixation as a standardized approach in selected MPL cases with tibial rotational deformity.

Keywords

medial patellar luxation - tibial internal rotation - dynamic external fixation - canine orthopaedics

Contributors' Statement

M.P. contributed to conceptualization, data curation, formal analysis, methodology, supervision, writing—original draft, writing—review and editing. L.V. contributed to data curation, formal analysis, methodology, writing—original draft, writing—review and editing. A.V. contributed to data curation, formal analysis, methodology, supervision, writing—original draft, writing—review and editing.

Ethical Approval

This retrospective study involved clinical cases treated at veterinary institutions. No experimental procedures were performed. Written informed owner consent for the use of clinical data was obtained, and approval was granted by the directors of the participating hospitals.

Publication History

Received: 18 May 2025

Accepted: 16 December 2025

Article published online:
07 January 2026

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